"auto_nodetitle" is a small and efficient module that allows hiding of the content title field in the form. To prevent empty content title fields one can configure it to generate the title by a given pattern.

When the token module is installed it's possible to use various node data for the
auto generated title - e.g. use the text of a CCK field (since 5.x).

Advanced users can also provide some PHP code, that is used for automatically generating an appropriate title.

Related module for Drupal 7:

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